Global Patent Index - EP 1698864 A4

EP 1698864 A4 20080312 - THERMAL FLOWMETER OF FLUID

Title (en)

THERMAL FLOWMETER OF FLUID

Title (de)

THERMISCHER STRÖMUNGSMESSER FÜR FLUIDE

Title (fr)

DEBITMETRE THERMIQUE POUR FLUIDES

Publication

EP 1698864 A4 20080312 (EN)

Application

EP 03774082 A 20031120

Priority

JP 0314789 W 20031120

Abstract (en)

[origin: EP1698864A1] A thermal air flowmeter having excellent temperature characteristics and improved measurement accuracy. The thermal air flowmeter comprises a temperature sensor (16) disposed in a casing (23) of the air flowmeter, a computing unit (17) for correcting a flow rate detection voltage from a measuring element (1) by using the temperature sensor (16), and heating temperature control means (6b) disposed in a temperature control circuit for performing temperature control of a heating resistor (5) to vary a temperature rise of the heating resistor (5) relative to an air temperature depending on the air temperature. Flow rate detection errors of the thermal air flowmeter caused by an overall temperature change and a temperature change on an intake passage wall surface can be corrected simultaneously and a thermal air flowmeter having superior measurement accuracy can be realized.

IPC 8 full level

G01F 1/68 (2006.01); G01F 1/00 (2006.01); G01F 1/684 (2006.01); G01F 1/696 (2006.01)

CPC (source: EP US)

G01F 1/6845 (2013.01 - EP US); G01F 1/6965 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR

DOCDB simple family (publication)

EP 1698864 A1 20060906; EP 1698864 A4 20080312; EP 1698864 B1 20150923; AU 2003284593 A1 20050608; CN 100408981 C 20080806; CN 1879010 A 20061213; JP 4558647 B2 20101006; JP WO2005050143 A1 20070614; US 2007125169 A1 20070607; US 7631555 B2 20091215; WO 2005050143 A1 20050602

DOCDB simple family (application)

EP 03774082 A 20031120; AU 2003284593 A 20031120; CN 200380110717 A 20031120; JP 0314789 W 20031120; JP 2005510760 A 20031120; US 58011203 A 20031120